Vacuum cleaners are generally used for removing dirt, litter, rubbish, scraps or other items more generally referred to as waste matter. The waste matter removed is usually stored temporarily in a waste collector inside the vacuum cleaner but would remain in the vacuum cleaner until the waste collector is emptied. The duration of this temporary storage varies and depends on the actual use.
Because of the inherent nature of waste matter and the varieties of matter that would reside in the waste collector, it is not unusual that unpleasant smells develop and disseminate to the ambient air from the vacuum cleaner. It is also not unusual that waste matter could stay inside a vacuum cleaner for weeks or even months before a waste collector is emptied.
Where the stored waste matter comprise bacteria degradable materials or matter suitable for bacteria growth, the vacuum cleaner will quickly become a potential source of health hazards as well as unpleasant odours. The dissemination of harmful bacteria into the ambient air may be aggravated by the accelerated exhaust air-stream of the vacuum cleaner which helps to spread bacteria in confined areas.
U.S. Pat. No. 4,554,698 issued to Rennecker proposed the use of a scent dispensing arrangement for use with an upright vacuum cleaner to alleviate the unpleasant smells associated with a vacuum cleaner. This proposed arrangement, however, only provides fragrance conditioning to the downmost exhaust air stream on exit from the vacuum cleaner. Un-pleasant smells and bacteria could escape through the air-permeable dirt collecting bag adjunct to the vacuum cleaner well before they reach the exit.
U.S. Pat. No. 5,461,751 issued to Sepke proposed putting a odourising agent or pesticide containing porous"tea bag" inside the dirt collector to neutralise the unpleasant smells and as a pesticide. However, because such a conditioning "tea bag" is placed inside the dirt collector and buried among waste matter, it will be discarded everytime when the dirt collector is emptied even though the item itself is still useful. In addition, as the "tea bag" is usually buried well inside the dirt collector, only waste matter in its vicinity can be conditioned. Furthermore, because the "tea bag" is stored together with the waste matter which is usually very dirty, it could not be conveniently removed or replaced even if it is realised that the contents of the tea bag reacts undesirable with the waste matter or a different odourising agent is required to provide a satisfactory conditioning.